Improve user's welcome to the community

[lucca65]

Today new users have no proper welcoming to the community: they lack knowledge about how to communicate with admins, no information about events or social media, no introduction. Cambiatus communities admins now relies on fully offline experiences to engage with their community.

We had a few discussions and ideas about this in the past:

• An improved footer element on issue https://github.com/cambiatus/frontend/issues/300 (@juramos-2020 first issue with us if I'm not mistaken)
• An draft for an welcome email on our backend

During development of cambiatus/backend#199 @adubas asked about our welcoming emails not being actively used, only implemented and this lead to this idea of improving the onboarding of our users

[lucca65]

@muguika @heltonlr @rafachadud I would love to hear your feedback about this idea!

[rafachadud]

I love those features mentioned above. And what do you @muguika @heltonlr @lucca65 think about a welcome modal for onboarding new users?
We can display a "carousel" modal, with maybe 3 messages for the user, introducing Cambiatus and the community.